help help help please help

blueflash

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Jan 2, 2006
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Age
49
Location
Paris Ontario Canada
Hi guys I used to ride alot but have parked my sled for the last 2 years. I have a 1998 yamaha srx. When I last rode it 2 years ago it ran perfect when I put it away, now its running weird. I cleaned out the carbs 2 times, checked the power valves, checked that its getting spark to all three cylinders. The problem is that when it sits at a idle it runs at about 3000rpm. If I want to get it moving I have to give it some choke until the rpms drop down to about 1500 then I can quickly turn the choke off and give it gas and it takes off like a bat out of hell. So long as I dont let the rpms drop below 5000 it runs strong, it they drop down below 5000, then it will probably give a good back fire , run irratically untill I give it some choke again and let the rpms drop down to 1500, then I can quickly turn off the choke and give it throttle again and it roars away. Help Help Help, I dont know what to do ??????
 
HMMM... Did some mice make it into your pipes and make it row housing for them...? just a guess
 
make sure that your pilots are absolutely clean. i thought mine were and it was idlin real high. that turned out to be my problem rechecked em and they had shit in em . carb cleaner toothpicks and compressed air did the trick ran fine after that. GOOD LUCK.
 
Do you think that if mice made it into my pipes then it would run horrible at 5000rpm or higher?? It runs normal above 5000 rpm, would then eventually burn out if I ran it for a bit or do I have to go through the trouble of taking them off?? The tank was close to empty but not totally empty, so I threw in 5 bucks of new gas, but again it runs excellent once it goes above 5000rpm. Dont know maybe I should take off the pipes and drop all of the fuel out, I just didnt want to get into all of that work if it wasnt necessary
 
check em pilots good.Put new plugs in to.Should of drained all the old gas off first and then cleaned carbs.You cleaned the carbs,added $5 of new gas,pushing some old gas back into the carbs and there you go..a problem again.
 
I took the pilots out and they were clean along with the little holes in the side. Do you think that I need to take them apart again and try to put a little piece of wire in were they screw into, is that what you mean by checking the pilots.
 
My Guess Is That One Of Your Crank Seals May Have Dried Out , Thus At Low Rpm You Are Running Lean , Pulling In Air , And When You Choke It It Adds Fuel To The Mixture , And At That Point You Are Able To Get Going , These Situations Are Not As Evident When On The Main Jet Circuit .. Hope For You Its A Carb Situation And Not Seals But If It Is Your Best To Fix It , Its Not A Lot Of $, Just A Little Time .
 
ya I read the carb cleaning part Im just not quite clear on the part about sticking a wire into were the pilot jet screws into, everything I read so far is making me think that the pilot jet is the problem but they are definetely clean, but I wasnt thorough with the part they screw into, I just quickly blew them out. I will take them off again tomorrow, and see if I can get any crud to come out of the place they screw into, How do you know if the part is clean that they screw into??? PS the girl is chasing me because I just blew snow on her
 
thanks for the info on the faq section I thought you were talking about something else, I see there is a part there about putting fluid through were it screws into to see if its dripping through, I didnt check that I will tomorrow, hopefully thats my problem. thanks again
 
Yes the part about cleaning were you cant see is very important.Use the little plastic hose that goes into a airisal can of carb cleaner\ wd40 something along this line.Do all the port openings as said .
 
You need to clean the entire idle cicuit, not just the pilot jets. There is a passage from the pilot jet to the fuel screw, and from the fuel screw into the venturi. Take the fuel screws out, then blow out the passages with compressed air and carb cleaner. When I did it, first I cleaned the pilots and it ran a little better but not good, then I blew air thru the pilot jet base and it ran a little better, then finally I took the fuel screws out and cleaned the whole thing and that did the trick.

If you want to test for air leaks though, while the engine is running spray carb cleaner around the crank seals and carb boots and anywhere else you suspect a leak. If there is a leak the engine should suck the carb cleaner in and the rpms should go up.
 
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Are you sure the carbs are seated in the boots well and that the mounting boots are not cracked? It sounds like a vaccum leak. How abou the line going from the port on the crankcase to the fuel pump? Ckeck to make sure it is not dried out and cracked and that it is seated on the nipple coming out of the crankcase. I'll keep thinking about it and look over my SRX for more ideas.
 
When you clean the carbs, use a blow gun and blow air through everything. Sounds like the carbs are pluged.
 
RTYsxv said:
You need to clean the entire idle cicuit, not just the pilot jets. There is a passage from the pilot jet to the fuel screw, and from the fuel screw into the venturi. Take the fuel screws out, then blow out the passages with compressed air and carb cleaner. When I did it, first I cleaned the pilots and it ran a little better but not good, then I blew air thru the pilot jet base and it ran a little better, then finally I took the fuel screws out and cleaned the whole thing and that did the trick.

If you want to test for air leaks though, while the engine is running spray carb cleaner around the crank seals and carb boots and anywhere else you suspect a leak. If there is a leak the engine should suck the carb cleaner in and the rpms should go up.
I would bet dollars its your pilot circut there are 4 orfices to go through(screw,pilot jet (hole)and one on the mouth(airbox side)and one in the venturi.Use an aresol carb/brake solvent with the straw.First blow down the jet hole and fluid should come through the other two(and into the venturi ) and will likely come back at you (Safety glasses).if not all three you'll know where your problem is,it could also be restricted) so blow through all the holes both ways with solvent and then with air!If your carbs are still on ,Try the solvent around the crank seal thing to eliminate that first....good luck
 
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